Knock sensor again...

[SpanishJohn]

Hi guys,

I'm kinda at a stage where I'm thinking my ks is not working (properly). I don't get the FI light but I do get the symptoms. When I ride in dry/hot conditions (i.e. pro-knock) I get a rattle/buzz at 3K-4K rpm. When I ride in moist cool conditions (i.e. anti-knock) my engine is smooth. Before anyone asks - yes I have changed my CCT, and if it was the CCT why the feck is it so smooth in moist conditions. As I said, I don't get the FI ligfht on start-up, but then again, I'm pretty sure the ECU isn't doing much apart from asking 'are you there' to the ks.

So, I was wondering if any of you could loan me a ks before i spend the 130 quid on a new part ;-0)).

Thx, Spanish

 

[Jaws]

But surely you fitted the X11 cct and that cured it ?
( get ready to replace the slippers as a good manyof the people who went down that route a few years ago have all now found out :-( )
Or are you know saying that maybe it was not the CCT ????

 

[SpanishJohn]

yes, I thoughg the x11 cct had cured it, but then again I was riding in fog (moist) so the engine was smooth :bang:. I may put the double green dot cct back in the bike.

Spanish

 

[Wolfie]

moist air is dense air, the bike runs better with dense air, says to me that your bike is over fueling.

 

[SpanishJohn]

moist air is dense air, the bike runs better with dense air, says to me that your bike is over fueling.

Maybe, but an over fuelled bike won't knock, an overly lean one may. Anyway, the level of soot on my stock cans is only slight.

Spanish

 

[Jaws]

yes, I thoughg the x11 cct had cured it, but then again I was riding in fog (moist) so the engine was smooth :bang:. I may put the double green dot cct back in the bike.

Spanish

Now completely baffled.. What has the amount of dots got to do with it ?
All that shows is that the body of the CCT was produced after 1998.. Nowt to do with the internals ..

 

[SpanishJohn]

Now completely baffled.. What has the amount of dots got to do with it ?
All that shows is that the body of the CCT was produced after 1998.. Nowt to do with the internals ..

Sorry John, I don't know why your confused - lets start again.

My XXY 2000 FI 20K mile BB has a strong buzz/vibe etc. at 3K rpm. The buzz/vibe etc gets progressively worse with engine temp and is also heavily dependent on air temp. So much so that riding in July/August became a no no :cry:. I natuarally assumed it was the CCT, so I replaced my double green dot CCT with a new one. The new CCT did not cure the problem, so in desperation I purchased a X11 cct. After fitting the X11 cct I took the bike for an 80 mile spin, but as luck would have it, the conditions were cool and damp. The result was a smooth ride with no problems. I assumed the problem to be cured, until the next time I rode the bike (dry warm day) when the buzz returned :bang:. This is why I am considering putting back my double green dot CCT over the X11 CCT as its clearly not a CCt problem. My bike obviously has a problem and my current thinking is the ks, hence the request....

Spanish

 

[SpanishJohn]

Can I also add that this is spoiling what would otherwise be a very capable bike, but trust me, if you rode the bike in mid july you would come back wanting to trade it. I bought the bike to tour on - but this is a no no at the moment. I have also spent loads of money and time trying to solve this problem. I even did the valve clearances last week hoping they would be out, but they weren't :bang:

Spanish

 

[Wolfie]

somewhere deep in the back of my mind some little light is on with wax unit on it, but for the life of me i can not remember where or either what forum i read it on.

PS it might of been on the yank one, but i aint sure sorry.

 

[SpanishJohn]

Thanks Wolfie, I though the wax unit only effects the engine at idle. My leaning now is stronly towards the ks, as knock usually occurs at 3K and would fit my problem. However I don't want to spend 137 quid on one hency my request for a loan one to verify my thinking.

I may borrow a scope from work and look at the waveforms coming out of mine, but problem is, I have nothing to compare them against.

Spanish

 

[Jaws]

I am confused by the references to a double dot CCT

Please explain what the dots have got to do with it ? ( or why you think they have something to do with the type of CCT used )

 

[Wolfie]

I am confused by the references to a double dot CCT

Please explain what the dots have got to do with it ? ( or why you think they have something to do with the type of CCT used )

he had a double dot on the bike, thought the vibes were the cct so changed it to a x11 cct.

but then found out that it was not the cct.

the bike knocks when hot or has a hot day.

when the air is damp or cool the bike is dead smooth.

that help??

 

[SpanishJohn]

John,

I bought a CCt from your good self, and it had two green dots on it. I then bought a X11 CCT from DS which was black. The black one is still on the bike, but I may put the one i got from you (the one with two green dots on it) back on after your comments on the chain guides... I'm sorry If I have confused you. But any way, forget CCT's as this is not the cause..

 

[Jaws]

LOL !! Ok.. Got it now !
It was all this green dot stuff.. I was reading it that you thought the double dot body was something special.. like I said, that only indicates the body was made after 1998 .. hence my not so much confusion but more bafflement !

 

[andyBeaker]

Just thinking out loud here and I am no expert but if the running changes with air temperature does this not suggest the fuelling is a bit out?? My old carb Bird was def sweeter when the temperature dropped - not noticed any change with the FI but only had that since March and still using summer gloves. I suspect the FI on a Bird is pretty rudimentary and possibly does not adjust itself much if at all based on outside temperature??

Not a cheap option, but if it comes down to fuelling would a Power Commander and set up help??

 

[silverfox.xx]

I doubt if its a knock sensor fault, do you get the F1 light giving code 25?

Do you/are you ok to do the fault test/reset of codes?, if so disconnect the Knock sensor and start the bike... F1 should give code 25 which you will need to reset after this test, you will also hear the engine running rougher... If it still sounds the same my bet its ECM breaking down.

Another thought is that maybe the ECM is on its way out, not behaving properly, as mine did 6 to 12 months before the KS fault/code 25 appeared as perminent, and that was not the KS but the ECM.

You'd probably be better off trying another ECM, before trying a KS in all honesty.

I have a spare KS however, but try the above first.

 

[SpanishJohn]

Hi Silverfox,

My feeling is the knock sensor is on its way out and is giving a weaker signal than normal to the ECU which would explain my probs. The ks is passing the ECU 'test', hence no code 25, but I suspect the 'test' is very minimal. The fact that it is pasing the test however also validates the ECU input curcuits. There is a slim chance its the ECU I agree, but then again the ECU input circuit is more likely to pack in all together as yours did, rather than gradually fade. Knock sensors, on the other hand, do have a finite life. The only real test is to replace the ks and take the bike for a good run in dry conditions (pro-knock) and see the difference. Would you be willing to loan me your spare ks?

Many thanks, Spanish

 

[smedly]

I agree, doubtfull on the KS, temp is an obvious indicator that you have mentioned many times, also what altitude are you based, atmospheric pressure may be a factor with the baro sensor, what oil do you use ? what milage is on your bike ? what air filter are you using ? the CCT is a distinctive buzz I rekon could be influenced with oil temp and viscosity, I am in a hot humid climate and I'm currently tweaking with the CCT as I get the buzz, I have a spare one that I'm manually adjusting the spring effectively strengthening it's effect, fitting it tomorrow, I also think it's the CCT that vibrates and buzzes not the cam chain, if you take a worn CCT out it rattles inside the body because all the parts seem loosen after a while of use.

 

[SpanishJohn]

I now realize why the ks wire is basically unshielded from the ks to the ECU. The ks is resonant so should generate voltage spikes in excess of 10V @ 1KHz over background noise, hence no need for shield. Problem is , as the ks ages its resonant freq can change by a few tens of Hz so the knock spike will be attentuated significantly.

Spanish

PS my bike is 100% stock bar an alarm.

 

[smedly]

It's the alarm..................100% sure, pull it out of the bike and all will be well

ahem.....

the KS is shielded and the frequencies you mention are wrong, without reservation - forget the KS, and it is shielded and earthed.

milage ?
oil ?
altitude ?

IAT sensor may also be a possibility.

a loose exhaust

pull the vaccum off the FPR also and check for fuel in there when the fuel rail is primed (turn on the ignition)


I understand that you think your engine is knocking but I very much doubt it